TECHNICAL FIELD
[0001] The present invention relates to a display for displaying high-resolution, wide-field
images.
BACKGROUND ART
[0002] Development of large-screen displays requires large-screen video contents.
Conventional displays display wide-field, high-resolution images that are produced
by taking wide areas in such a manner that individual imaging areas are overlapped
using a plurality of cameras.
As a technique of producing the wide-field, high-resolution images, there is one,
for example, which matches images taken with a wide-view camera like a fisheye camera
and images taken in detail with a plurality of common cameras (images obtained by
taking partial areas of the imaging area of the wide-view camera), and transforms
the images taken with the plurality of common cameras in such a manner as to bring
them together with the image taken with the wide-view camera (see Patent Document
1, for example).
This makes it possible to produce images equivalent to the wide-field images at high-resolution.
[0003] However, the conventional display is for displaying the wide-field, high-resolution
images on a single display, and not for displaying on a multi-display consisting of
a plurality of displays.
For this reason, when displaying images on a large screen, they are displayed on a
display with a large screen area. However, since the resolution of displays has the
limits of technology (resolution of displays on the market is generally only 1920
× 1080 as a standard), the high-resolution display has its limits .
[0004]
Patent Document 1: Japanese Patent Laid-Open No. 2004-135209 (Paragraph [0008], and FIG. 1)
[0005] With the foregoing configuration, the conventional display can produce and display
wide-field, high-resolution images on the display. However, the images are displayed
on a single display, and not displayed on a multi-display composed of a plurality
of displays. For this reason, when displaying the images on a large screen, they are
displayed on a display with a large screen area. However, since the resolution of
the display has the limits of technology, there is a problem in that the high-resolution
display has a limit.
[0006] The present invention is implemented to solve the foregoing problem. Therefore it
is an object of the present invention to provide a display capable of large-screen
display of wide-field, high-resolution images.
DISCLOSURE OF THE INVENTION
[0007] A display according to the present invention is configured in such a manner that
it includes a plurality of area identifying means for identifying areas corresponding
to partial areas taken with partial imaging means in an imaging area taken with a
wide-view imaging means; image projection means for projecting images of the partial
areas taken with the plurality of partial imaging means onto image spaces of the areas
identified by the area identifying means; and rectangular area dividing means for
synthesizing overlapped areas of the images of the plurality of partial areas projected
by the image projection means, and for dividing the image after the synthesis to a
plurality of rectangular areas, wherein a plurality of distortion correcting means
correct distortion of the images of the partial areas taken with the partial imaging
means in accordance with the rectangular areas to which the rectangular area dividing
means divides, and display images after the correction on displays.
[0008] This offers an advantage of being able to carry out a large-screen display of wide-field,
high-resolution images.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
FIG. 1 is a block diagram showing a configuration of a display of an embodiment 1
in accordance with the present invention;
FIG. 2 is a flowchart showing processing contents of the display of the embodiment
1 in accordance with the present invention;
FIG. 3 is a diagram showing positional relationships of cameras 2a - 2f, second image
processing units 4a - 4f and displays 5a - 5f;
FIG. 4 is a diagram showing a manner of projective transformations of images of partial
areas taken with the cameras 2a - 2f onto image spaces of areas specified by a matching
section 15 (image spaces of areas corresponding to the partial areas in the imaging
area taken with a wide-view camera 1);
FIG. 5 is a diagram showing examples of an overlapped area;
FIG. 6 is a diagram showing a manner of synthesizing overlapped areas in a horizontal
direction;
FIG. 7 is a diagram showing cross areas of overlapped areas;
FIG. 8 is a diagram showing a manner of creating a rectangular areas;
FIG. 9 is a block diagram showing a configuration of a display of an embodiment 2
in accordance with the present invention;
FIG. 10 is a flowchart showing processing contents of the display of the embodiment
2 in accordance with the present invention;
FIG. 11 is a diagram showing points eligible for a reference point; and
FIG. 12 is a diagram showing scanning termination in rectangular search processing.
BEST MODE FOR CARRYING OUT THE INVENTION
[0010] The best mode for carrying out the invention will now be described with reference
to the accompanying drawings to explain the present invention in more detail.
EMBODIMENT 1
[0011] FIG. 1 is a block diagram showing a configuration of a display of an embodiment 1
in accordance with the present invention. In FIG. 1, a wide-view camera 1, which corresponds
to a common digital video camera provided with a wide-angle lens, for example, takes
a prescribed imaging area at a wide view. Incidentally, the wide-view camera 1 constitutes
a wide-view imaging means.
Cameras 2a, 2b, 2c, 2d, 2e and 2f, which correspond to a common digital video camera
with a visual field narrower than the wide-view camera 1, take individual partial
areas in the imaging area taken with the wide-view camera 1. Incidentally, the cameras
2a, 2b, 2c, 2d, 2e and 2f constitute a partial imaging means.
[0012] A first image processing unit 3 acquires an image of the imaging area taken with
the wide-view camera 1, and executes prescribed image processing.
Second image processing units 4a, 4b, 4c, 4d, 4e and 4f acquire images of the partial
areas taken with the cameras 2a, 2b, 2c, 2d, 2e and 2f, correct the distortion of
the images of the partial areas, and execute processing of displaying on displays
5a, 5b, 5c, 5d, 5e and 5f.
Although the example of FIG. 1 shows an internal configuration of the second image
processing unit 4a, internal configurations of the second image processing units 4b,
4c, 4d, 4e and 4f are the same as that of the second image processing unit 4a.
Incidentally, although the components of the first image processing unit 3 and second
image processing units 4a, 4b, 4c, 4d, 4e and 4f can be constructed from dedicated
hardware, the first image processing unit 3 and second image processing units 4a,
4b, 4c, 4d, 4e and 4f can be constructed from a common general-purpose personal computer,
and programs describing the processing contents of the individual components can be
stored in a memory of the general-purpose personal computer so that the CPU of the
general-purpose personal computer executes the programs.
[0013] An image acquiring section 11 of the first image processing unit 3 acquires the image
of the imaging area taken with the wide-view camera 1, and executes processing of
writing the image in an image memory 12.
The image memory 12 of the first image processing unit 3 is a memory for storing the
image of the imaging area taken with the wide-view camera 1.
[0014] An image acquiring section 13 of the second image processing unit 4a acquires the
image of the partial area taken with the camera 2a, and executes processing of writing
the image in an image memory 14.
The image memory 14 of the second image processing unit 4a is a memory for storing
the image of the partial area taken with the camera 2a.
[0015] A matching section 15 of the second image processing unit 4a executes matching processing
for identifying in the imaging area taken with the wide-view camera 1 the area corresponding
to the partial area taken with the camera 2a, that is, matching processing for identifying
the area corresponding to the partial area by extracting feature points from the image
of the imaging area stored in the image memory 12 and from the image of the partial
area stored in the image memory 14, and by search for the feature points corresponding
to each other.
A projective transformation information calculating section 16 of the second image
processing unit 4a executes processing of calculating projective transformation information
used for projecting the image of the partial area taken with the camera 2a onto the
image space of the area identified by the matching section 15.
Incidentally, the matching section 15 and the projective transformation information
calculating section 16 constitute an area identifying means.
[0016] A projective transformation section 17 of the first image processing unit 3, using
the projective transformation information calculated by the projective transformation
information calculating sections 16 of the second image processing units 4a, 4b, 4c,
4d, 4e and 4f, executes the processing of projecting the images of the plurality of
partial areas onto the image spaces of the corresponding areas. Incidentally, the
projective transformation section 17 constitutes an image projection means.
[0017] An overlapped area searching section 18 of the first image processing unit 3 executes
the processing of searching for the overlapped areas of the images of the plurality
of partial areas projected by the projective transformation section 17.
An overlapped area synthesizing section 19 of the first image processing unit 3 executes
the processing of synthesizing the overlapped areas of the images of the plurality
of partial areas searched for by the overlapped area searching section 18.
A rectangular area dividing section 20 of the first image processing unit 3 executes
the processing of dividing the image after the synthesis by the overlapped area synthesizing
section 19 into a plurality of rectangular areas.
Incidentally, the overlapped area searching section 18, overlapped area synthesizing
section 19 and rectangular area dividing section 20 constitute a rectangular area
dividing means.
[0018] A distortion correcting parameter table creating section 21 of the second image processing
unit 4a executes the processing of creating a distortion correcting parameter table
from the projective transformation information calculated by the projective transformation
information calculating section 16 on the basis of the rectangular areas resulting
from the division by the rectangular area dividing section 20.
A distortion correcting section 22 of the second image processing unit 4a, referring
to the distortion correcting parameter table created by the distortion correcting
parameter table creating section 21, corrects the distortion of the images of the
partial areas stored in the image memory 14, and executes the processing of displaying
the image after the correction on the display 5a.
Incidentally, the distortion correcting parameter table creating section 21 and distortion
correcting section 22 constitute a distortion correcting means.
FIG. 2 is a flowchart showing the processing contents of the display of the embodiment
1 in accordance with the present invention.
[0019] Next, the operation will be described.
The wide-view camera 1 in the present embodiment 1 has a wide-angle lens attached
to the common digital video camera, and its resolution is assumed to be 1920 × 1080.
The cameras 2a, 2b, 2c, 2d, 2e and 2f are arranged so as to take the individual partial
areas in the imaging area of the wide-view camera 1 as shown in FIG. 3, in which they
are placed in an arrangement of roughly 2 × 3 in the vertical and horizontal directions.
The resolution of the cameras 2a, 2b, 2c, 2d, 2e and 2f is assumed to be 1920 × 1080.
In addition, the displays 5a, 5b, 5c, 5d, 5e and 5f are placed in a grid-like fashion
in 2 × 3 in the vertical and horizontal directions as shown in FIG. 3, in which their
arrangement agrees relatively with the positions of the partial areas taken with the
cameras 2a, 2b, 2c, 2d, 2e and 2f. The resolution of the displays 5a, 5b, 5c, 5d,
5e and 5f is assumed to be 1920 × 1080.
[0020] As for the resolution of the cameras 2a - 2f and the resolution of the displays 5a
- 5f, even if they are set without any correlation, no problem occurs.
In the present embodiment 1, although the numbers of the cameras, second image processing
units and displays are each assumed to be six, a configuration is also possible in
which their numbers are increased without any limitation as long as their relative
positional relationships are maintained.
[0021] In the initial state, since the correcting parameters for correcting the distortion
of the images taken with the cameras 2a - 2f have not been created (step ST1), the
creating processing of the correcting parameters is started.
First, the wide-view camera 1 takes a prescribed imaging area at a wide view (step
ST2), and outputs the image of the imaging area to the first image processing unit
3.
The image acquiring section 11 of the first image processing unit 3 acquires the image
of the imaging area output from the wide-view camera 1, and executes the processing
of writing the image in the image memory 12.
[0022] The cameras 2a - 2f also take the individual partial areas simultaneously with the
wide-view camera 1 (step ST2), and output the images of the partial areas to the second
image processing units 4a - 4f.
The image acquiring sections 13 of the second image processing units 4a - 4f acquire
the images of the partial areas output from the cameras 2a - 2f, and execute the processing
of writing the images in the image memories 14.
[0023] The matching sections 15 of the second image processing units 4a - 4f acquire the
image of the imaging area taken with the wide-view camera 1 from the image memory
12 of the first image processing unit 3 (step ST3).
In addition, the matching sections 15 execute matching processing for identifying
in the imaging area taken with the wide-view camera 1 the areas corresponding to the
partial areas taken with the cameras 2a - 2f, that is, matching processing for identifying
the areas corresponding to the partial areas by extracting feature points from the
image of the imaging area taken with the wide-view camera 1 and from the images of
the partial areas stored in the image memories 14, and by search for the feature points
corresponding to each other (step ST4).
[0024] The matching processing is a method of extracting the feature points from the individual
images, and considering the feature points having information similar to each other
as the same points.
For example, a method called SIFT (Scale-invariant feature transform) extracts the
feature points of the image of the imaging area taken with the wide-view camera 1
and the feature points of the images of the partial areas taken with the cameras 2a
- 2f as 128-dimentional vectors, and carries out matching by considering the feature
points with small Euclidean distances as the same points.
Incidentally, as for the extracting method of the feature points, it is not limited
to SIFT. For example, a detecting method of using a Harris operator can be used, or
a feature point extracting method such as "Speeded up robust features" can be used
instead.
[0025] The projective transformation information calculating sections 16 of the second image
processing units 4a - 4f calculate the projective transformation information used
for projecting the images of the partial areas taken with the cameras 2a - 2f onto
the image spaces of the areas identified by the matching section 15 (the image spaces
of the areas corresponding to the partial areas in the imaging area taken with the
wide-view camera 1) (step ST5). Thus, they calculate the coordinate transformation
information (projective transformation information) from the image spaces of the cameras
2a - 2f to the image space of the wide-view camera 1. For example, they calculate
the coordinate transformation information (projective transformation information)
according to a plane projective transformation.
The plane projective transformation can be expressed by a 3 × 3 matrix, and it is
known that the coordinate transformation information (projective transformation information)
can be calculated if there are four or more corresponding groups between the coordinates
before transformation and the coordinates after the transformation.
Accordingly, if four or more pieces of the matching information (groups of the feature
points considered to be the same points) can be acquired from the matching section
15, the coordinate transformation information (projective transformation information)
from the image spaces of the cameras 2a - 2f to the image space of the wide-view camera
1 can be calculated.
[0026] Incidentally, the matching information output from the matching section 15 can sometimes
contain a lot of errors, and if the matching information is applied to the calculation
of the plane projective transformation, the accuracy of the coordinate transformation
can sometimes be impaired.
For this reason, when the projective transformation information calculating section
16 calculates the coordinate transformation information (projective transformation
information) according to the plane projective transformation, it is desirable to
increase the accuracy of the coordinate transformation by calculating by adding a
Robust method (such as the least squares method, M estimation, and "Random Sample
Consensus").
Although an example of calculating the coordinate transformation information (projective
transformation information) according to the plane projective transformation is explained
here, the method is not limited to it. For example, it is also possible to calculate
the coordinate transformation information (projective transformation information)
by a linear transformation such as scaling and translation on an Euclidean space or
by a general transformation such as affine transformation.
[0027] The projective transformation section 17 of the first image processing unit 3 collects
the projective transformation information calculated by the projective transformation
information calculating sections 16 of the second image processing units 4a, 4b, 4c,
4d, 4e and 4f (step ST6).
In addition, the projective transformation section 17, using the projective transformation
information calculated by the projective transformation information calculating sections
16 of the second image processing units 4a, 4b, 4c, 4d, 4e and 4f, projects the plurality
of the images of the partial areas onto the image spaces of the corresponding areas
(step ST7).
[0028] FIG. 4 is a diagram showing a manner of projective transformation of the images of
the partial areas taken with the cameras 2a - 2f onto the image spaces of the areas
identified by the matching sections 15 (image spaces of the areas corresponding to
the partial areas in the imaging area taken with the wide-view camera 1).
As for the four coordinates at the endpoints of the image spaces of the cameras 2a
- 2f, that is, (0, 0), (1919, 0), (0, 1079) and (1919, 1079), the projection can obtain
their coordinate values on the image space of the wide-view camera 1 by individually
transforming them using six projective transformations transmitted.
Incidentally, it is assumed that the point at the upper left corner of the image is
(0, 0), and that the coordinate values increase as they go further right in the horizontal
direction and lower in the vertical direction.
[0029] The overlapped area searching section 18 of the first image processing unit 3 searches
for overlapped areas of the images of the plurality of partial areas (images of the
six areas) after the projection when the projective transformation section 17 projects
the images of the plurality of partial areas onto the image spaces of the corresponding
areas (step ST8).
FIG. 5 is a diagram showing an example of the overlapped areas.
It searches for the overlapped areas for each two vertically and horizontally adjacent
areas.
As shown in FIG. 5(a), when the two areas overlap vertically, it searches for, as
the overlapped area, an area between the y coordinate of the uppermost point of the
bottom side of the upper rectangle and the y coordinate of the lowermost point of
the top side of the lower rectangle.
In addition, as shown in FIG. 5(b), when the two areas overlap horizontally, it searches
for, as the overlapped area, an area between the x coordinate of the leftmost point
of the right side of the left rectangle and the x coordinate of the rightmost point
of the left side of the right rectangle.
[0030] When the overlapped area searching section 18 has searched for all the overlapped
areas, the overlapped area synthesizing section 19 of the first image processing unit
3 synthesizes the overlapped areas adjacent to each other vertically and horizontally
(step ST9). The synthesis of the overlapped areas is carried out for each row or column
of the overlapped areas.
FIG. 6 is a diagram showing a manner of synthesizing the overlapped areas in the horizontal
direction.
[0031] When the overlapped area synthesizing section 19 has synthesized the overlapped areas,
the rectangular area dividing section 20 of the first image processing unit 3 divides
the image after the synthesis into a plurality of rectangular areas (step ST10).
Details of the concrete processing of the rectangular area dividing section 20 are
as follows.
First, as shown in FIG. 7, the rectangular area dividing section 20 obtains cross
areas of the overlapped areas synthesized by the overlapped area synthesizing section
19, and selects any two adjacent cross areas.
As for a display arrangement of 2 × 3 regions in the vertical and horizontal directions,
there are only two cross areas. However, as for a display arrangement of m × n regions
in the vertical and horizontal directions, since there are (m-1) × (n-1) cross areas
in general, two adjacent cross areas are selected from them.
From each of the two cross areas selected, one point is selected, and the points are
made reference points.
The reference points must have the same y coordinate when the cross areas are adjacent
in the horizontal direction, and have the same x coordinates when they are adjacent
in the vertical direction.
[0032] Next, the rectangular area dividing section 20 creates rectangular areas of the number
of displays in accordance with the reference points.
FIG. 8 is a diagram showing a manner of creating the rectangular areas.
As for the creation of the rectangular areas, it creates a rectangular area in such
a manner as to employ the line segment across the two reference points as a side and
to have the aspect ratio of the displays 5a - 5f, and covers the regions with the
rectangular areas in the same manner as the arrangement of the displays 5a - 5f.
Here, since the resolution of the displays 5a - 5f is 1920 × 1080, the rectangles
are formed so as to maintain 16:9.
[0033] After creating the plurality of rectangular areas, the rectangular area dividing
section 20 outputs the rectangular areas as the final division rectangular information
if conditions are satisfied that all the cross points of the four rectangles are contained
in the cross areas and the whole rectangular areas are within the camera area.
Unless the foregoing conditions are satisfied, it selects two reference points again,
and carries out the similar processing.
The rectangular information about the division thus obtained is transmitted to the
second image processing units 4a - 4f (step ST11) .
Incidentally, the rectangular information about the division consists of the upper
left coordinate values and the lower right coordinate values of the rectangle.
[0034] Receiving the rectangular information about the division from the rectangular area
dividing section 20, the distortion correcting parameter table creating sections 21
of the second image processing units 4a - 4f, using the rectangular information, create
the distortion correcting parameter tables from the projective transformation information
calculated by the projective transformation information calculating sections 16 (step
ST12).
The concrete processing contents of the distortion correcting parameter table creating
sections 21 are as follows.
First, using the rectangular information transmitted from the rectangular area dividing
section 20 and the coordinate information at the four corners of the displays 5a -
5f, the distortion correcting parameter table creating sections 21 obtain projective
transformation P from the coordinate systems of the displays 5a - 5f onto the image
coordinate system of the wide-view camera 1.
More specifically, they obtain the projective transformation P as corresponding points
of the four points (0, 0), (1919, 0), (0, 1079), (1919, 1079) of the displays 5a -
5f and the four points (dsx, dsy), (dex, dsy), (dsx, dey), (dex, dey) of the division
rectangular area.
[0035] Next, the distortion correcting parameter table creating sections 21 obtain inverse
transformation of the projective transformation information calculated by the projective
transformation information calculating sections 16, and obtain projective transformation
invH from the image coordinate system of the wide-view camera 1 onto the image coordinate
systems of the cameras 2a - 2f.
Next, the distortion correcting parameter table creating sections 21 obtain composite
transformation invH·P of the projective transformation invH and the projective transformation
P.
Incidentally, the composite transformation invH·P corresponds to the projective transformation
from the coordinate systems of the displays 5a - 5f onto the image coordinate systems
of the cameras 2a - 2f.
[0036] Using the composite transformation invH·P makes it possible to correct the distortion
of the images taken with the cameras 2a - 2f and to display them on the displays 5a
- 5f.
The correcting parameters are created from the tables, and applying the composite
transformation invH·P to all the coordinates of the displays 5a - 5f from (0, 0) to
(1919, 1079) makes it possible for all the pixels of the displays 5a - 5f to obtain
which pixels of the cameras 2a - 2f they refer to.
[0037] The distortion correcting sections 22 of the second image processing units 4a - 4f
correct, when the distortion correcting parameter table creating sections 21 create
the distortion correcting parameter tables, the distortion of the images of the partial
areas stored in the image memory 14 by referring to the distortion correcting parameter
tables (step ST13 and ST14), and display the images after the correction on the displays
5a - 5f (step ST15).
[0038] This enables the displays 5a - 5f to display the images with the same contents as
the image taken with the wide-view camera 1 at a high resolution.
Incidentally, once the correcting parameter tables have been created, the same correcting
parameter tables can be used as long as the settings of the cameras 1 and 2a - 2f
and of the displays 5a - 5f are maintained. Accordingly, from this point forward,
the displays 5a - 5f can display the images after the distortion correction without
executing the processing of creating the correcting parameter tables every time the
cameras 2a - 2f take the partial areas.
[0039] As is clear from the foregoing description, according to the present embodiment 1,
since it is configured in such a manner that it includes the plurality of matching
sections 15 for identifying the areas corresponding to the partial areas taken with
the cameras 2a - 2f in the imaging area taken with the wide-view camera 1, the projective
transformation section 17 for projecting the images of the partial areas taken with
the cameras 2a - 2f onto the image spaces of the areas identified by the matching
sections 15, the overlapped area synthesizing section 19 for synthesizing the overlapped
areas of the images of the plurality of partial areas projected by the projective
transformation section 17, and the rectangular area dividing section 20 for dividing
the image after the synthesis to a plurality of rectangular areas, and that the plurality
of distortion correcting sections 22 correct the distortion of the images of the partial
areas taken with the cameras 2a - 2f in accordance with the rectangular areas resulting
from the division by the rectangular area dividing section 20, and display the images
after the correction on the displays 5a - 5f, it offers an advantage of being able
to display wide-field, high-resolution images on a large screen.
Thus, it offers an advantage of being able to display the images passing through the
distortion correction easily without restriction on the configuration and number of
the displays, and to carry out the high-resolution display without any limitation
on the resolution of the displays.
EMBODIMENT 2
[0040] FIG. 9 is a block diagram showing a configuration of a display of an embodiment 2
in accordance with the present invention. In FIG. 9, since the same reference numerals
as those of FIG. 1 designate the same or like portions, they description will be omitted
here.
A rectangular area storage section 23 stores the rectangular areas resulting from
the division by the rectangular area dividing section 20. Incidentally, the rectangular
area storage section 23 constitutes a rectangular area storage means.
A rectangular area selecting section 24 selects, from the rectangular areas stored
in the rectangular area storage section 23, a rectangular area meeting a prescribed
condition (for example, a condition for selecting the maximum rectangular area, a
condition for selecting the minimum rectangular area, and a condition for selecting
a rectangular area closest to the center of the imaging area taken with the wide-view
camera 1), and outputs the rectangular information about the rectangular area to the
distortion correcting parameter table creating sections 21 of the second image processing
units 4a - 4f. Incidentally, the rectangular area selecting section 24 constitutes
a rectangular area selecting means.
FIG. 10 is a flowchart showing processing contents of the display of the embodiment
2 in accordance with the present invention.
[0041] Next, the operation will be described.
In this case, however, since it is the same as the foregoing embodiment 1 except that
it has the rectangular area storage section 23 and rectangular area selecting section
24, the operation of the rectangular area storage section 23 and rectangular area
selecting section 24 will be described mainly.
[0042] In the foregoing embodiment 1, although the rectangular area dividing section 20
selects the total of two reference points, each from the two cross areas, and makes
a decision as to whether the rectangle can be divided or not, the present embodiment
2, using the point at the upper left corner of a single cross area as a first reference
point, scans all the points that can become a reference point on the second cross
area adjacent thereto, and makes a decision for each point as to whether the rectangular
can be divided.
As for the points eligible for a reference point, it is necessary as in the foregoing
embodiment 1 that the y coordinates are the same when the cross areas are adjacent
horizontally, or the x coordinates are the same when they are adj acent vertically.
FIG. 11 is a diagram showing the points eligible for a reference point.
[0043] The rectangular area dividing section 20 stores, during the scanning and if the rectangular
division is possible, the coordinate values of the rectangular area into the rectangular
storage section 23 as the rectangular information about the rectangular area divided.
Since the decision as to whether the rectangular division is possible or not is the
same as the foregoing embodiment 1, the detailed description thereof is omitted here.
When the scanning within a range eligible for the second reference point has been
completed, followed by a decision as to whether the rectangular division is possible
or not, the first reference point is moved by one pixel next, and the same processing
of moving the second reference point is carried out.
When completing the decision as to the rectangular division for all the points within
the cross area to which the first reference point belongs after successively executing
the foregoing processing, the rectangular search processing by the rectangular area
dividing section 20 terminates (see FIG. 12).
[0044] When the rectangular search processing by the rectangular area dividing section 20
has been completed (step ST21), the rectangular information about the plurality of
rectangular areas is stored in the rectangular area storage section 23 (step ST22)
.
The rectangular area selecting section 24 selects from the rectangular areas stored
in the rectangular area storage section 23 the rectangular area meeting the condition
for selecting the maximum rectangular area, for example (step ST23), and outputs the
rectangular information about the rectangular area to the distortion correcting parameter
table creating sections 21 of the second image processing units 4a - 4f (step ST11).
[0045] As a method of selecting the maximum rectangular area, a method is conceivable which
compares the widths of the rectangular areas in the plurality of rectangular areas
and selects one with the greatest width.
Although an example that selects the maximum rectangular area is shown here, it is
not limited to that. For example, the condition can be set for selecting the minimum
rectangular area or for selecting the rectangular area closest to the center of the
imaging area taken by the wide-view camera 1, and the minimum rectangular area or
the rectangular area closest to the center of the imaging areas can be selected.
In addition it is also possible to select the rectangular area to be kept at the leftmost
edge or the rectangular area to be kept at the rightmost edge.
INDUSTRIAL APPLICABILITY
[0046] As described above, the display in accordance with the present invention is suitable
for displaying a high-resolution, wide-field image on a large screen.